i) Field of the Invention
This invention relates to a novel alcohol-modified silicone ester derivative (hereinafter referred to simply as silicone ester derivative) and cosmetic compositions containing same.
ii) Description of the Background Art
Silicone oils are widely used as an oil ingredient for cosmetic compositions due to their excellent lubricity, water repellency, gloss imparting capability, stability, safety, etc. Among them, a high molecular dimethylpolysiloxane has generally been used in the art. The dimethylpolysiloxane, however, raises a problem when incorporated in a cosmetic composition. It gives disagreeable feel to the skin. In detail, it gives creaky feel when that of low viscosity is used and sticky feel when that of high viscosity is used. Moreover, it is accompanied by an another problem in that an emulsion system is difficult to obtain because the high molecular dimethylpolysiloxane has poor compatibility with hydrocarbon oils.
With regard to the art focusing on the above problem of the high molecular dimethylpolysiloxane, there are two publications which are Japanese patent applications laid-open to the public, Kokai 61-129187 and Kokai 63-150288. They disclose esterified products between dimethylpolysiloxanediol and a dibasic acid or between dimethyl polysiloxanediol and a long-chain fatty acid, respectively. These compounds, however, still demand improvement of feel on use and blendability.
The present invention was made primarily to overcome the above-mentioned drawbacks of the silicone oils by taking an approach quite different from those disclosed in the mentioned publications, and to develop a novel silicone derivative having excellent properties which were never obtained from the conventional silicone oils, and further to develop cosmetic compositions having agreeable feel on use.
The present inventors carried out an earnest study focusing on the above goals and found that an alcohol-modified silicone ether derivative of formula (I) had a good compatibility with other solvents, gave agreeable feel upon use and was free from the drawbacks accompanied by the conventional silicone oils. Such findings have led to the completion of this invention.